warp.utils.runlength_encode#

warp.utils.runlength_encode(
values,
run_values,
run_lengths,
run_count=None,
value_count=None,
)[source]#

Perform run-length encoding on an array.

This function compresses an array by replacing consecutive identical values with a single value and its count. For example, [1,1,1,2,2,3] becomes values=[1,2,3] and lengths=[3,2,1].

Parameters:

  • values (array) – Input array to encode. Must be of type int32.

  • run_values (array) – Output array to store unique values. Must be at least value_count in size.

  • run_lengths (array) – Output array to store run lengths. Must be at least value_count in size.

  • run_count (array | None) – Optional output array to store the number of runs. If None, returns the count as an integer.

  • value_count (int | None) – Number of values to process. If None, processes entire array.

Returns:

Number of runs if run_count is None, otherwise returns the run_count array.

Raises:

RuntimeError – If array storage devices don’t match, if storage size is insufficient, or if data types are unsupported.

Return type:

int | array